Taycan 4S tuning - hypothetically

[RAHRCR]

Every car manufacturer has to find the balance between performance, reliability, and efficiency when it comes to their power plant. There is also a marketing/sales angle if they intend to offer models at multiple price points. For the Taycan, I would be hesitant to modify…at least this early in the life cycle of this product. In an ICE vehicle, it is much more clear as to what the risks are when making mods. My biggest concern would be how the software would interpret the modification and integrate that info with the other systems on board. For a vehicle built on new architecture, I am going to wait and see for at least a generation before considering mods to the powerplant(s).

Sponsored

 

[Simoniz]

Hi

According Porsche web pages Taycan CT 4 and Taycan CT 4S share the same front and rear motors and inverters. I think It’s only the matter of time when some tuning firm will remap the Taycan 4 CT ecu. I think there will be many potential customers…

 

[Rcrewse7]

Received an update from Steinbauer Engineering this morning stating that they are working towards a Spring release for the Taycan 4S tuning module, with more details to be forthcoming. Will keep you all posted.

Latest update suggests that development is proceeding well with details available in May.

 

[ChronoMax]

Im sure there will eventually be an aftermarket interface to access all the proprietary functions such as diagnostics, communication / telemetry / privacy, module coding, and of course updates / modding. The market for this will be exactly zero until its a proven product and factory warranties start to expire.

 

[whan]

I wonder if the torque in the RWD is detuned as well. Feels a bit light that it only makes 263 lb-ft but 469hp. In comparison a Tesla model 3 RWD makes 302lb-ft and 221hp and a Mach E RWD 306lb-ft/255hp. Because the Taycan delivers relatively higher hp vs. torque, in my mind it feels that the taycan's torque curve is relatively flat, and potentially software capped at lower RPM for quite a while.

My understanding is that EV powertrains deliver max torque at 0RPM and can hold it there for lower RPMs for a short period, but drops off rapidly at higher RPM. While still at max torque, HP builds linearly with RPM (see Tesla dyno graph in link)

https://fossbytes.com/tesla-model-3-sr-vs-long-range-dyno-run/

Again, compared to other RWD EVs where torque often is a lot closer to the HP figure, this implies that the Taycan holds max torque a much larger range of RPMs. This is echoed by acceleration tests of the Taycan RWD. Its lower speed acceleration is slower than competitors, (0-60 in 4.7 to 5.0 depending on rollout) but ends up with a pretty quick trap speed in the 1/4 of 115mph

Part of me wonders if that's hardware or software limited. If hardware, what decisions did Porsche make that cause it to be able to hold torque for so much longer, but why is peak torque lower than competitors?

If software, has porsche limited the instant torque on the RWD to incentivize stepping up to a 4S? No matter what the 4S will be significantly faster with two motors, but wondering if the RWD did 0-60 in 4.5ish (without rollout), if less people would step up to a 4S doing it in 3.5 (assuming it wasn't detuned either)

 

[whan]

More musings about potential Porsche software detuning of the lower level Taycans. Comparing a RWD specifically to a Model Y Performance, both make similar peak power of ~470hp (using the Model 3 dyno here as a proxy https://insideevs.com/reviews/401474/tesla-model-3-standard-performance-dyno/)

The Model Y does make more torque at 400-420 lb-ft vs. RWD 263. BUT, the Taycan is geared a lot shorter in 1st, at ~15:1, while the Model Y is at 9:1. In reality, this should make up for the torque differential at the wheels (263*15/9=438, pretty similar when adjusting for gearing).

Recall from the graph in my last post that EV max torque is provided at low RPMs up until a certain RPM, from which it then tapers off. In order for the motor in the Taycan RWD to produce 470hp at only 263lb-ft, it implies that it should be holding max torque for a longer period of time to higher RPMs vs. the Tesla, as that's the only way it makes sense (power being torque * RPM * constant). The Tesla makes peak power at near max torque at ~5700 motor RPM which = ~55MPH at 9:1 gear ratio. Based on published figures, the Taycan should be making peak power at a similar MPH despite a 15:1 gear ratio, given it's able to produce peak power using lower peak torque (Need to rev to 52% higher at max torque vs having a 66% shorter gear ratio)

Because of this gearing difference, you'd expect the Taycan to have somewhat of a similar 0-60 time as the Tesla Y Performance (at least low 4s if not high 3s) given similar-ish weight, HP, gearing-adjusted, but that's not the case. I feel like this is only explained by Porsche not providing the peak torque on launch at 0rpm that it is capable of. Quite a few reviewers have noted that there's not an initial shove in the RWD you get from EVs, but that it builds pretty quickly afterwards, or even once on the move for passing power.

 

[Rcrewse7]

Latest update suggests that development is proceeding well with details available in May.

Sounds like development took a bit longer than expected, however they are reporting that they will wrap up in late July. Fingers crossed, as I’m anxious to see what kind of extra performance they are able to squeeze.

On another note, I had seen that Manhart, a German tuning company, had developed a tune for the Tesla Model 3 Performance, and reached out to them regarding tuning the Taycan. They quickly responded and appear to have something up their sleeves for the Taycan in 2023.

With some luck, there will be a couple of tuning options coming out over the next few months for us Taycan owners who are so inclined.

 

[Simoniz]

Sounds like development took a bit longer than expected, however they are reporting that they will wrap up in late July. Fingers crossed, as I’m anxious to see what kind of extra performance they are able to squeeze.

On another note, I had seen that Manhart, a German tuning company, had developed a tune for the Tesla Model 3 Performance, and reached out to them regarding tuning the Taycan. They quickly responded and appear to have something up their sleeves for the Taycan in 2023.

With some luck, there will be a couple of tuning options coming out over the next few months for us Taycan owners who are so inclined.

Very much looking forward to it.

 

[whan]

Was somewhat bored and doing some bench racing in excel, analyzing acceleration data from AutotopNL's videos for the Taycan RWD PBP and Model Y Performance that include breakdowns of 0-100kmh and 100-200kmh. Charts are below

Two interesting observations:

• I believe the RWD's acceleration is artifically capped from 0-50kmh. It's surprisingly consistent at 0.5 seconds per 10kmh, whereas the Tesla actually shows decreasing intervals up until 40kmh.
  • In the context of EVs, the Tesla's numbers make more sense. EV motors provide max torque at 0RPM, and HP produced rises as the motors wind up to speed until peak power is produced. This explains why the Tesla actually is accelerating faster and faster up to 40kmh, and after this point peak HP is reached and starts to taper off slowly
  • Perhaps this is also an effect of the car hooking up and getting traction, but in this case you'd expect the Taycan being RWD should benefit even more from this effect
• The Taycan RWD shift point is around 130kmh. It is audible in the video, and also reflected by the sudden change in the acceleration intervals from ~0.75s to ~1.05s

As a hypothetical, if you took the MYP's % changes in intervals and applied it to the Taycan's 0-10kmh, you'd get a table that looks like this, resulting in a 4.4s 0-100kmh. This is actually a lot closer in-line with what you'd expect from a car with this power and weight

Source videos here:

 

[Jhenson29]

In the context of EVs, the Tesla's numbers make more sense. EV motors provide max torque at 0RPM, and HP produced rises as the motors wind up to speed until peak power is produced. This explains why the Tesla actually is accelerating faster and faster up to 40kmh, and after this point peak HP is reached and starts to taper off slowly

HP rising as speed increases doesn’t mean accel gets faster. Under constant torque, accel should be constant, assuming negligible changes to resistance.

Torque applied at the wheel becomes a force and acceleration equals force times mass. So constant force = constant acceleration. HP increases because you’re doing work at a faster rate as you accelerate. But that doesn’t necessarily mean faster acceleration. For acceleration to increase, HP would have to increase faster than the rate of speed, meaning torque would be increasing.

 

[f1eng]

1 ) The wiring will be the same for all cars (4S, T, TS). This means the diameter of the conductors. This means the same potential energy transfer within the conductors.

The wiring isn't the same for all models. Nor are the inverters.

Your assumption then is that the cooling system is somewhat different between the 4S and the T+TS?

The cooling system will certainly differ in that the T and TS both have a bigger rear motor which has a bigger water jacket. Heat transfer to the cooling water will therefore be greater. Whether this gives a real gain depends on the coolant flow rates and heat exchanger performance (and ambient temperature).

Feels a bit light that it only makes 263 lb-ft but 469hp. In comparison a Tesla model 3 RWD makes 302lb-ft and 221hp and a Mach E RWD 306lb-ft/255hp.

The torque you extract from an electric motor depends on the current capacity of the wiring and how much current you send and this is mainly limited by how hot you are prepared to let the motor and wires get.
Power is torque times speed and is the key parameter for overall performance but a big blob of torque low down is good for drag racing because you don't need it for long - because you can't have it for long before causing damage.

 

[whan]

HP rising as speed increases doesn’t mean accel gets faster. Under constant torque, accel should be constant, assuming negligible changes to resistance.

Torque applied at the wheel becomes a force and acceleration equals force times mass. So constant force = constant acceleration. HP increases because you’re doing work at a faster rate as you accelerate. But that doesn’t necessarily mean faster acceleration. For acceleration to increase, HP would have to increase faster than the rate of speed, meaning torque would be increasing.

Ah you're totally right - I forgot that Power = M*A*V

I found an interesting video on youtube from an italian channel (with eng subs) that dyno'd the RWD taycan and turbo, as well as showing previous Telsa model 3 dyno. Not sure what to make of it exactly, but interesting that the RWD hits peak torque at a later RPM than the Turbo, and also hits peak power at a significantly later point




@f1eng, would there be any hardware limitation that causes the RWD to hit peak torque later? I understand issues with heat in prolonged peak torque output, but not sure if anything is limiting the RWD peak torque from being hit sooner

 

[Jhenson29]

would there be any hardware limitation that causes the RWD to hit peak torque later?

Not asked but…not really. Torque is proportional to current at that point and current is what causes heating. The only time this is typically an issue is when the cooling system is driven by the rotor and is not effective at low RPM, which wouldn’t be the case with the car.

 

[Schn3ll]

Seriously? Have you never been around car enthusiasts before?

 

[whan]

Not asked but…not really. Torque is proportional to current at that point and current is what causes heating. The only time this is typically an issue is when the cooling system is driven by the rotor and is not effective at low RPM, which wouldn’t be the case with the car.

Makes sense, hence I'm wondering if the RWD and possibly 4S are leaving performance on the table at low speeds, with Porsche tuning down the ramp to peak torque vs. what is actually possible on the hardware

Sponsored